1. Technical Field
The present invention is in the field of go karts. In particular, the present invention relates to tools used during the checking and setting up of the go kart, i.e. to tools used during the maintenance of the go kart and during the adaptation of the go kart to a particular race track. Further in particular, the present invention relates to tools relying on optical measurements.
2. Background Information
Go karts are a very basic kind of race cars. They are mainly used for recreational racing purposes. Also, go karts are used by children and adolescents who wish to enter the field of car racing. In particular, go karts are viewed as a stepping stone for developing driving skills before moving on to professional car racing classes like Formula 3®, GP 2®, and Formula 1®.
Typical go karts have a chassis, which forms the base of the go kart. In particular, the chassis forms the support for the other components of the go kart, such as the driver's seat, the engine, the steering mechanism, the wheels, the bumper frame, aerodynamic structures, etc. The correct alignment of the chassis is an important factor for a good driving behaviour of the go kart. If the chassis is bent or twisted, this can quickly lead to undesired driving characteristics of the go kart.
The driving characteristics of the go kart are further heavily influenced by the set up of the steering mechanism of the go kart. The user of the go kart has various degrees of freedom to set up the steering mechanism. The four most commonly used adjustment options are camber, toe in/out, caster, and king pin angle. Camber refers to the inclination of the front wheels with respect to their vertical orientation. Toe in/out refers to the degree of deviation of the wheel orientation from the longitudinal extension of the go kart. The wheels pointing towards the inside is referred to as toe in, whereas the wheels pointing towards the outside is referred to as toe out. In other words, toe in and toe out refer to the deviation of the rolling direction of a front wheel from the straight rolling direction, if the wheel were to roll unrestrained by the go kart. Caster refers to the rotation of the front wheel axis, to which the front wheel is mounted, and its point of suspension. In case the front wheel axis is suspended by a king pin, caster refers to the inclination of the king pin towards the front or back. While caster does not have an impact on the go kart during straight driving, it provides for a relative lifting or lowering of the wheel, when the steering is turned. This results in desired shifts in weight and force absorptions during cornering of the go kart. The inclination of the king pin towards the left or right, i.e. the inclination with respect to the imaginary connection line between the front axles of the go kart, is referred to as the king pin angle. While the camber of the steering mechanism may be affected by the king pin angle, it is possible that the king pin angle is zero and that camber is achieved in a different manner. In other words, there is not necessarily a direct relation between the king pin angle and the camber value.
As the chassis alignment and the steering mechanism set up play an important role in achieving good driving characteristics of the go kart, with the optimum being different from track to track depending on the layout, grip level, etc., a variety of tools for checking the chassis alignment and gauging the steering mechanism are in use. In recent years, optical measurement devices, often relying on laser technology, have become common place. However, available tools are still not fully satisfactory.
In particular, the available tools for measurement of the caster angle and/or the king pin angle are still very cumbersome to use. They require multiple steps of operation and do not allow for quick measurements.
Accordingly, it would be beneficial to provide an improved go kart steering measurement tool that allows for a particularly quick measurement of the caster angle and/or the king ping angle of the steering mechanism and is easy to use.